Apparatus for implanting medicinal pellets subcutaneously



June 27, 1950 2,513,014

M. R. FIELDS APPARATUS FOR IMPLANTING MEDICINAL PELLETS SUBCUTANEOUSLYFiled Nov. 18, 1946 [72092257 mack E fE'Z'ai'' A, 9 W

Patented June 27, 1950 APPARATUS FOR IMPLANTING MEDICINAL PELLETSSUBGUTANEOUSLY v Mack R. Fields, Chicago, Ill., assi'gi'ior to AbbottLaboratories, of Illinois North Chicago, 111., "a corporationApplication November 18, 1946, Serial No. 710,621

' g invention relates to apparatus for implanting medicinal pelletssubcutaneously.

'In the treatment oi: pertain ailments 'by the use i oftherapeutic'ag'ents such as hormone principles,

penicillin. streptomycin; and possibly other medicinal elements. it ishighly desirable to maintain within the body a so-called' tissuefiuidsand blood level of the'medicationin fixed proportions for aprolongedperiod. Most medicinal agents of the character indicated tend to di aterapidly through absorptioninto the body'iiuids, thereby necessitating afrequent administration'of the desired medicinal agents in order tomaintain the desired blood level. It has been found that it is possibleto prepare medications of the type-above is present in the blood streamand tissue fluids at a required level 01 a period of several days;

The objects of the present invention are to provide a simple and easilymanipulated means for implanting medicinal pellets subcutaneously; toprovide such means whereby handling of the individual pellets is"avoided with attendant benefits in respect of the preservation of thesterile or aseptic condition of the pellets; and to provide an improvedpellet package whereby distribution of pellets of therapeutic agents'ofthe character indicated in-sterile or aseptic condition-is greatlfacilitated. 1

Other objects and advantages of the invention will be understood byreference to the following specification and accompanying drawing inwhich there is illustrated a selected form of'the apparatus and aselected form of pellet package embodying the invention.

In the drawing:

Figs. 1 and 2 are side and end views respectively of a needle structure,

Fig. 3 is a side view partially in elevation and partially in section ofa pellet package or cartrid'ge, and

Fig. 4 is a sectional illustration of the manner in which the pelletcartridge of Fig. 3 and the needle structure of Fig. 1 are employed forthe In some cases it v 2 Claims. (Cl. 1-28.2 17) purpose ofsubcutaneously implanting medicinal pellets supplied to the physician inthe packaged form illustrated in Fig. 3.

For, penetrating the tissues, a needle I isemployed, the said needlebeing a tubular member having a bevelled or sharpened end 2 At the otherend, the needle I is provided with anenlar'gement or head 3 which issuitably secured rigidl ron the blunt end portion of the needlepreferably in co-axial relation thereto. The head is fcounterbored fromits free outer or rear end as indicated at 4 for a purpose whichwillpresently appear. v H

A stylet or removable core 5 is associated with the needle I, saidstylet having a bevelled end portion 6 which isnormal-ly in co-planarrelation to the bevelled end 2 of the needle I. Said stylet 5 is of adiameter which fits slidably within the lumen I of the needle so thatthe stylet tmay be readily inserted and withdrawn from the needle. Theother end of the stylet is provided with a laterally bent end portion 8,andthe head 3 0f the needle isprovided with a radially extending groove9 for receiving said stylet end portion 8 to thereby rotatably positionthe stylet in the needle with the bevelled ends of the stylet and needlein th desired co-planar relationship.

The pellet cartridge shown in Fig. 3 comprises a tubular andpreferrably'a transparent body If] having abore l l of substantially thesame diameter as the diameter of the lumen I of the needle. "Somevariation is permitted in this respect, but it is preferable thatthesediameters beapproximately the same so that pellets such .asrepresented at l2 and I3 fitting slidably in the bore of the cartridgebody will also be slidable through the lumen of the needle. For closingthe ends of the tubular cartridge body It, caps or end closures l4 -M ofrubber or other suitable material, preferably resilient material, areapplied to the cartridge ends as shown. These caps l4l4 are preferablyof such size that they may be stretched when applied to the cartridgeends to such an extentthat they will frictional-1y grip the cartridgebody end portions to thereby retain themselves in place while at thesame time being readily removable when desired.

At one end, the cartridge body is provided with a flaring mouth entranceIt to the bore l I therein to facilitate insertion of the pellets suchas l2 and stylet whichprojects beyond the flattened edge 18 ofthe head,servetoindicatejthe position of the bevel of ,the. .nee'dle..Whentheneedle has been inserted to the proper position, the stylet theneedle.

I 3 into the body. As represented in Fig. 3, the

pellets I3 are about. twice the length of the pellet I2. Other lengthrelationship may, of course, be employed depending upon the dosagerequired.

With the described apparatus, medicinal pellets may be implanted underthe skin as follows:

The assembled needle and stylet I and 5 in the relationship shown inFig. 1 is first inserted through the tissues to.locate the bevelleddischarge end of the needle at the required place under the tissues.During insertion of the needle,

the physician :(.or;.nurse) holds the head of the needlebetween theindex and middle fingers while placing the thumb against the rear end ofthe head in overlying relation to the laterally extending end portion 8of the stylet. By so holding the needle, the stylet-is held againstrearward displacement during the insertion of the needle. The head is ofgenerally cylindrical.form having a suitably grooved jor recessedcentral annular portion I6 to facilitate holding of the needle betweenthe index and middle fingers, and a rear flange portion I1 of the headhas flattened edge portions I8 and I9 which are preferably arranged inplanes which are parallel to the gen- .eral: plane of the bevelled. endsof the needle and stylet. The groove 9 in (the rear end of the needlehead and the portion of .the bent end. 8-of the withdrawn leaving thehollowneedle in place.

' hump in the patients skin just when withdrawal of the needle shouldbegin so as to leave the pellets in the desired location. Also, thelength of plunger remaining between the outer or free end of thecartridge body and the adjacent portion of the eye ZI constitutesanother indicator as to when withdrawal of the needle should begin. Itwill be observed that said distance between the cartridge and plungereye is always equal to the combined length of the pellets remaining inthe discharge end portion of the needle? I I 'I-To facil itate thepassage of pellets from the cartridge I0 into the lumen of the needle I,the

ntrance end of the lumen is flared as indicated at 23. I n theconstruction shown, the entrance end of the needle I communicatesdirectly with -the*counterbore 4. This, of course, may be modified to:provide theflared mouth 23 in a portion of the. head--"3,'the needlereceiving recess then terminatin sshortof the bottom of thecounteriPresent manufacturing equipment and processesdndicate that thesmallest diameter to which pellets of therapeutic agents of the kindreferred to may be made is about 0.85 inch (slightly more than of aninch).,--the length'being Variable I but preferablynot muchQmore than aof arrinch.

.A cartridge Ill containing the desired pellet (or pellets) is thenprepared for assembly with .-.the. ,needle by removing one of the endcaps I4, and then inserting the open end of the cartridge body into therecess or socket 4 provided for that 'purpose in the head of .theneedle. The cartridge- .body [0 is preferably of-cylindrical formcorre-,

sponding to thecylindricalcounterbore 4, and of ,ansexternal diameterwhich will. fit snugly in said counterboreso that when oneend portion ofthe cartridge is inserted into the counterbore, the cartridge will bepositioned with its bore I l in the desired co-axial relationship tothe'lumen I of Thereupon the otherend closure. is removed from thecartridgeand a plunger or pistonlfl (Fig. 4) is inserted intoand throughthe a cartridge body and into and through the needle I.

,The piston 2!] may consist of a length of wire pl adiameter whichwillfit freely through the hereof the cartridgeand the lumen of theneedle and it isprovided with an eye 2| for facilitating,handling-thereof. Thepiston and eye are made so that when the end 22'of the piston reachesia predetermined relationship to the bevelled endof the needle as represented in dotted lines at2 2a, move-' ment of thepiston will be stopped by engagement of a portion of the eye :ZIwith-the then outer end of the cartridge I0. As the piston is advanced,the pellets I2 and I 3 will, of course, be fed forwardly through and outof the cartridge and through the lumenof the needle. When the leadingpellet reaches the bevelledend-of the needle and the tissue barrierclosing the same;

movement of the piston is stopped and the needle is withdrawn while thepiston is, in effect, held stationary so as to causethepellets to bedischarged from the needle, thepellets being thereby deposited in thespace vacated by the needle before the muscular tissue (or fat) canreturn toits normal position and close saidspace. ,-Physicians andothers experienced in .matters ;of this 1 kind.v a determ n byithe'formationof-i a-yisibl Theneedle I to handle,pelletsofthatsizewilL-onthe basis of-pre'sentpractical manufacturing .procedures, haveanexternial diameter of -about 1 12 inch. For insertionofa needle ofthat size itis, of course, preferable, if..not necessary, that the 7affected body .part be-initially treated withasuitable anesthetic .to,prevent excessive -pain. It

.should, however, beunderstoodthat as manufacturingequipment andprocesses improve; the indicated. dimensions maybe reduced .to .the endthat ;a. smaller needle :may be, v employed EWlthout .requiring the useof a ;local anesthetic.

Various changesin the .describedstruc'turemay bemade without-departingfrom the spirit -of the invention as'defined in the claims in this'application.

I claim 2-,

1. Apparatus forimplanting a pellet'subcutane- 'ously, comprising anelongated hollow ne'edle and -a;stylet extending through said needle,said needle and stylet having complementary-sharpenedends fortlssue--penetrati0n purposes, said needle having an enlarged'head onitsrear end needle and stylet ,havingcoplanar bevel-sharpened ends fortissue penetration purposes, said needle .having an venlarged head onits rear .end

, substantiallycoaxial withsaid needle .and provided with a socket incoaxial communication-with the .lumen 0f said needle,'said socket beingof substantially larger diameter thanthe 2111111811 of 75,.$a ;,nees 1,an ada t d e iv ja n 0 tion of a pellet cartridge from which a pelletmay be advanced into and through said needle,

the rearmost portion of said head having a flattened side portion and,in its rear face,'a slot extending radially of said head from saidflattened 5 MACK R. FIEIDS.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name I Date 1,655,158 Muir Jan; 3, 19281,960,858 Strauch May 29, 1934 2,009,393 ,Failla July 30, 1935 2,176,041Pittenger Oct. 10, 1939 2,426,535 Turkel Aug. 26, 1947 OTHER REFERENCESMedical Journal and Record, vol. CXXII, July-Dec. 1925; pages 227-229,article by P. E. Durham. A copy, is in the Army Medical Library atWashington, D. C. V

